As you can imagine, new technologies have brought many changes to the performance of server class CPUs beginning from the Pentium era. CPU performance itself has historically been measured by clock speed and front side bus of the processor. Clock speed is the speed at which a microprocessor executes instructions. The front side bus is the digital pathway connecting the CPU to the motherboard. Higher bus speed means faster communication with the rest of the system.

In 1993, the original Pentium featured a clock speed of 60 MHz and a front side bus speed that ranged from 60-66 MHz. Three years later, the Pentium II would boast clock speeds that ranged from 233-450 MHz and front side bus speed that ranged from 66-100 MHz. Many breakthroughs happened in the early 2000s. The Pentium 4 boasted a clock speed of 1.3 GHz and a front side bus speed of 400 MT/s. With X86 server virtualization in 2001, VMware and other virtualization technologies enabled multiple operating systems, and their related processes, to be run in parallel on a single CPU.

Amazon’s EC2 and Cloud Computing 1.0 was introduced in 2006—but it was rooted in Amazon’s ambiguous definition of CPU performance, making it more difficult for consumers to understand what exactly they were getting. This changed in 2012 with the introduction of Cloud Computing 2.0. It restored transparency and consistent performance to CPU performance.

To learn more, check out the infographic below!